Microwaves for the treatment of sterile ready meals
The increase in ready-meal consumptions (i.e. cold cuts, ready salads and sauces) has reached record values compared to all other food products. At the same time, meals away from home have increased considerably. To respond to this encouraging trend, food industry tried to exploit microwave technology for the production of sterile meals. We are talking of main courses like pasta, meat, and vegetables, available for selling in vending machines, with the scope of replacing company canteens and reducing management costs as well. Furthermore, the rise in ready-meals consumptions reflects changes in the structure of Italian families and in consumption habits compared to the past, as well as the increasing number of working couples. Among the main ready-meal consumers, there are six million singles in Italy. The advantage of a sterile product certainly is that of simplifying product logistics and cutting costs. Many attempts in this direction have been made in the past, with very few positive results, due to the limits listed above. Only in the last few years, technology has been refined and combined with other technical solutions, which allowed some companies to present themselves on the market with innovative products.
Sterile ready-meals processing-Description
The technology for processing sterile ready meals with Mo integrates an initial phase for the preparation of the various ingredients in a traditional industrial kitchen: here, ragouts, tomato sauce, broth, meats etc. are prepared. In a second phase, the food is deposited and assembled with the plate inside the container, which will be used as final end-user package; the container is then sealed with heat-sealed film; inert gas is introduced inside the package to remove the oxygen, which may spoil the product along its life cycle (oxidation). At this point the product is fed into the Mo-sterilization tunnel (see picture 1). Microwaves are used to complete the product cooking and its sterilization. By means of adequate waveguides and the special shape of the processing cavity, microwave power is conducted and distributed evenly inside the cavity, allowing the homogeneous heating of the product, with both continuous and discontinuous working cycles. The oven is made of four connected modules, forming a steel chamber inside which the magnetrons are installed. The transport of the packaged product inside the tunnel is continuous, with the assistance of overpressure to prevent the package from bursting or losing its tightness due to the steam generated inside the package. The four treatment phases are:
• product feeding module;
• air/water cooling module;
• three thermal treatment modules, divided in: microwave preheating; microwave heating and cooking (temperature > 121°C); maintaining the sterilization temperature.
Product infeed and exit modules are designed to reduce electromagnetic emissions produced by the microwave system in compliance to existing laws.
Evolutions of the microwave sterilization system
The described system was a flop in the past, due to the impossibility of ensuring the attainment of the sterilization temperature throughout the whole package. The evolutions of this technology implement a combined system with Mo and hot air that is blown on the product. Air is heated by an array of electric resistances, and sucked and blown inside each module by a centrifugal fan. The hot-air speed and blowing power can be electronically adjusted by changing the rotation speed of the fans by means of inverter. For each module an air temperature-humidity-speed diagram can be created, ideal for different types of thermal treatments, from sterilization to pasteurization, from thawing to drying, or for processing products with different needs.
Hot air is evenly blown throughout the whole module; the hot air hits both the bottom (hot air is blown through the holes of the conveyor belt) and top surface of the product. In this kind of continuous tunnel system, even the microwave power can be “punctually” adjusted for an even heating of the product . This combined system with hot air and microwaves is patented; it ensures excellent temperature uniformity and considerable heat exchange, for a quick heat transfer while minimizing thermal differences between the different areas of the treatment chamber.
Other food-related applications
Microwave technology is now used also for: fat-free cooking of snacks, such as chips and cheese; drying of fruit and vegetables; quick sterilization and pasteurization of any kind of loose or packaged product; quick sterilization of corn, rice, maize, nuts and hazelnut flour.
*Documentation supplied by courtesy of BI.ELLE Srl
Life form and Cancer.
I do have a theory that upon ingesting food that contains radio waves, it will cause
the Cancer cells to go into a starvation mode and be inactive than the cells will repair the infected area with some healing medication.
THIS IS MY THEORY.
ANY OPINION?
Ben.
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